The impact of external feedback on computer-assisted learning for surgical technical skill training

BACKGROUND: Computer-assisted learning (CAL) offers a number of potential advantages for surgical technical skills teaching. The purpose of this study was to evaluate the impact of individualized external feedback on surgical skill acquisition when a CAL package is used for instruction. METHODS: Freshman and sophomore students participated in a 1-hour CAL session designed to teach them how to tie a two-handed square knot. One group received individualized external feedback during the session and the other group did not. Subjects were videotaped performing the skill before and after the session. The tapes were independently analyzed, in blinded fashion, by three surgeons. Three measures were obtained: the total time for the task, whether or not the knot was square, and the general quality of the performance using a rating scale. RESULTS: Data from 105 subjects were available for final analysis. For both groups there were significant increases in the proportion of knots that were square when the posttest performance was compared with the pretest performance but there was no difference between groups on this measure. Comparison of the performance scores demonstrated that both groups had a significant improvement after the session but the performance scores were significantly better in the group that had received feedback. CONCLUSIONS: Novices in both groups using CAL showed improvement in two of the outcomes measured, suggesting that subjects in both groups attained some degree of competence with this skill. The higher posttest performance score for the group receiving feedback demonstrates that external feedback results in a higher level of mastery when CAL is used to teach surgical technical skills.     

Comparison between double-filtration plasmapheresis and immunoadsorption plasmapheresis in the treatment of patients with myasthenia gravis

Two techniques for plasmapheresis are used in the treatment of myasthenia gravis (MG): immunoadsorption (IA) and double filtration (DR). This controlled study evaluated the differences between these techniques in clinical effects and serological changes. Five patients with generalized MG (clinical states IIb and III) were enrolled; each patient received IA and DF plasmapheresis on separate occasions. Immunosorba TR-350 with an affinity to acetylcholine receptor antibodies (AchRAb) was used for IA, while Evaflux 4A was used as the plasma fractionator for DF. Each course of treatment consisted of five sessions of apheresis. MG score, titers of AchRAb, immunoglobulins (IG), and plasma biochemistry were assessed by blinded examiners before and immediately after the entire course of treatment. Both treatments effectively ameliorated symptoms of MG. There were no significant changes in MG score between the two groups (IA vs. DF: 2.2 vs. 2.6, P>0.5). IA had a higher clearance rate of AchRAb than DF (66 % vs. 54 %, P<0.05), while DF removed more IgA (72 % vs. 21 %, P< 0.05) and IgM (89 % vs. 57 %, P<0.01) than did IA. Although IA removed AchRAb more effectively than DF, the clinical effects between these two treatments were similar. The titers of AchRAb cannot reflect the clinical severity. Some circulating factors other than AchRAb may contribute to the pathogenesis of MG. Received: 10 September 1999, Received in revised form: 7 February 2000, Accepted: 24 February 2000     

Recurrent corneal perforation and acute calcareous corneal degeneration in chronic graft-versus-host disease.

Keratoconjunctivitis sicca (KCS) is a common complication of graft-versus-host disease (GVHD), and may lead to corneal epithelial defect and melting. In contrast, recurrent corneal calcareous degeneration and perforation is rare. A 46-year-old woman developed chronic GVHD after bone marrow transplantation for aplastic anemia. Severe KCS with corneal melting and calcium deposits were noted in the left eye. Penetrating keratoplasty was performed because of corneal perforation, but poor re-epithelialization and calcium deposition recurred. Lamellar keratectomy and amniotic membrane transplantation (AMT) were performed, but acute calcareous degeneration developed with subsequent recurrence of corneal perforation. After regraft, AMT and tarsorrhaphy, the corneal graft remained clear for 3 months. However, breakdown of the corneal epithelium occurred 3 weeks after spontaneous separation of tarsorrhaphy. Six months later, corneal perforation recurred again along with exacerbation of GVHD. Regraft was performed, but the patient refused tarsorrhaphy and AMT. Poor re-epithelialization persisted after regraft. Corneal melting with impending corneal perforation ensued. Further corneal surgery was refused and the patient chose to undergo evisceration. This case demonstrates that the ocular complications of GVHD may be severe enough to lead to corneal perforation and calcareous degeneration that is recalcitrant to medical and surgical treatment.     

Healthy Taiwanese Eating Approach (TEA) toward Total Wellbeing and Healthy Longevity

A healthy dietary pattern review for Asian countries is scarce, which is crucial for guiding healthy eating. We reviewed Taiwanese dietary pattern discovery studies. Included were 19 studies, the majority of which employed dimension reduction methods to find dietary patterns associated with various health conditions. To show what is a high or low intake of foods in Taiwan, we also report the average dietary content and the 25th and 75th percentile values of the adult population for six food groups gathered by the Nutrition and Health Survey in Taiwan, 2017–2020. The healthy Taiwanese dietary approach is cohesive across multiple health outcomes occurring at different ages. It is featured with higher intakes of plant-based foods, aquatic foods, and some beneficial ethnic foods (soy products), drinks (tea), and cooking methods (boiling and steaming); lower intakes of fast foods, fatty and processed meats, sugar, salt rich foods/drinks, and fried foods; but with mixed findings for dairy and egg. Yet, the average Taiwanese person consumed many refined staple foods and livestock, but not sufficient vegetables, fruits, whole grains and roots, beans, and nuts. Dairy consumption remains low. In conclusion, Taiwanese discovery studies point to a mortality-lowering total wellbeing dietary pattern consistent with the current knowledge, which discloses potential benefits of soy product, tea, and boiling and steaming.     

Soybean oil emulsion administration during parenteral nutrition in the preterm infant: effect on essential fatty acid, lipid, and glucose metabolism

To examine the effect of a soybean oil emulsion on essential fatty acid, lipid, and glucose metabolism, preterm infants were randomized to receive 0.5 g/kg/d lipid for 5 days (n = 10, group 1) or 0.5 increased to 2.0 g/kg/d over 5 days (n = 11, group 2). Triene/tetraene ratios did not change in group 1, but decreased in group 2. In both groups, plasma phospholipid linoleate (percent and micrograms per milliliter) increased, the increase being greater in group 2. In both groups, percent content of arachidonate and 5,8,11-eicosatrienoate decreased, and that of oleate remained unchanged. In contrast, absolute content of arachidonate and oleate tended to increase, and that of 5,8,11-eicosatrienoate remained unchanged. At a lipid intake of 0.5 g/kg/d, no infants had hyperlipemia. When lipid intake exceeded 1.0 g/kg/d, the frequency of hypertriglyceridemia (triglycerides greater than 200 mg/dL) and free fatty acidemia, with the free fatty acid/molar albumin ratio exceeding 6:1, increased. Plasma glycerol increased slightly, but was substantially less than the rise in enzymatically determined triglycerides. Hyperglycemia was self-limiting and did not require alteration in dextrose intake. Thus, (1) infusion of a soybean oil emulsion at 0.5 to 2.0 g/kg/d maintains essential fatty acid status and phospholipid arachidonate concentrations; (2) significant hyperlipemia occurs when lipid intake exceeds 1.0 g/kg/d; (3) hyperglycemia associated with lipid infusion tends to be self-limiting and may not require alteration in lipid or dextrose intake; and (4) enzymatically determined triglycerides may be used to monitor lipid tolerance, provided that allowance is made for a small but systematic overestimation resulting from the rise in plasma glycerol.     

Tumor necrosis factor-alpha converting enzyme in the human placenta throughout gestation

Ectodomain shedding of epidermal growth factor receptor ligands such as transforming growth factor- alpha (TGF-alpha), heparin-binding epidermal growth factor-like growth factor (HBEGF), and amphiregulin (AREG) is considered to be important during implantation. Tumor necrosis factor-alpha converting enzyme (TACE) has been suggested as the major sheddase for these molecules. The objectives of this study are (1) to characterize the expression of TACE in the human placenta throughout gestation; (2) to determine the association between the expression of TACE with TGF-alpha, HBEGF, and AREG; (3) to ascertain whether TACE mediates TGF-alpha, HBEGF, and AREG shedding; and (4) to examine the effect of hypoxia on the expression of TACE. By analyzing a total of 55 villous samples representing different gestational ages, the authors found that TACE was continuously expressed in the placentas throughout gestation and that the levels of TACE were positively correlated with the levels of TGF-alpha, HBEGF, and AREG. Preadministration of a TACE inhibitor in villous explant cultures or transfection of cytotrophoblastic cells with TACE-specific small interference RNA decreased the shedding of HBEGF and AREG. Moreover, hypoxia (2% O(2)) caused an increase in the levels of TACE mRNA and protein in villous explants and primary cytotrophoblastic cells in vitro. These results indicate that oxygen regulates the expression of TACE and that TACE may be important for placental development during human pregnancy.     

Abnormally low expression of connexin 37 and connexin 43 in subcutaneously transplanted cryopreserved mouse ovarian tissue

Purpose

To analyze the gap junction proteins connexin 37 (Cx37) and connexin 43 (Cx43) after subcutaneous transplantation of cryopreserved mouse ovarian tissue.

Methods

Expression of gap junction genes was assessed by immunohistochemistry and real-time polymerase chain reaction (PCR) in transplanted cryopreserved ovarian tissue compared with that of normal ovarian tissue. Apoptosis of ovarian cells was evaluated by using the terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphates nick end-labeling method.

Results

After subcutaneous transplantation, Cx37 and Cx43 mRNA and protein expression were significantly lower in cryopreserved than in normal ovarian tissue. Apoptosis was increased in granulosa cells from antral follicles of the cryopreserved tissue.

Conclusion

After cryopreservation and subcutaneous transplantation of ovarian tissue, proteins forming gap junctions between oocytes and granulosa cells are under-expressed compared with normal controls.